After reading the article this one actually requires a cable, which isn't as clean as the schlumpf systems. The heel clicking method shouldn't be much of a problems after a few days.
This seems to be the first one that's 3 speed.
My folding bike photo essays www.dekter.net/
Hopefully more competition means lower prices.
Easy Shift Schlumpf plates screw under the pedal and improve the arc that you can hit the button.
Stamped and polished, it covers the whole arm and so you have more contact situations, for better or worse..
I didn't install the pair that came on my Mountain drive .
if anyone wants them . My crank: Year old, straight 170 arms.